Removable permutation-lock



(Model.)

R, W. T HURMAN. REMOVABLE PBRMU'TATION LOCK.

. Patented J an. 1,7, 1882;.

ILINQrri;

rarns f PATENT einen..

ROBERT THURMAN, OF LYNGHBURG, VIRGINIA.

REMovVABLE PERM UTATIoNLocK.

.SPECIFICATION forming part of Letters Patent No. 252,336, dated JanuaryI7, 1882,

Application tiled November 17, 1881. (Model.) 4

To all whom it may concern:

Be it known that I, ROBERT W. THURMAN,

`a citizen of the United States of America, re-

siding at Lynchburg, in the county of Campt of this specification.

-sponding parts.

My invention consists in so constructing the locks of safe, vault, andsimilar doors thatl in case of accident the lock can he removed andthe'door opened without injur to either door or lock, avoiding theexpense, delay, and inconvenience incidental to the present method ofopening doors having combination-locks when the same are out of order.

In the accompanying drawings, Figure l. is ai front view of a portion ofa safe-door showing the application of my device. Fig. 2 is a verticallongitudinal section on the line 2 2,Fig. 1. Fig. 3 is a sectional viewon the Iine33ot'Fig-2.

Similar letters of reference indicate carre In the drawings, Arepresents a cylindrical shell or case, of metal, constructed in twoportions secured together, thc front portion being larger in diameterthan the rear. Each of the portions contains a separateand distinctpermutation-lock, N and O, of any known style having circular tumblers.The spindles of both these locks are brought to the front end of theease, the spindle I) of the front or secondary lock, N, being madehollow to permit the spindie B of thc rear lock to be operated throughit as though it. were not there.

On the outer end of spindle B is the ordinary dial-plate, D, operated asusual underneath. Concealed by the dial D is a smaller dial, C, foroperating the secondary lock N, which is unaffected by theordinaryoperation of lock There is a sot, F, in the case A, extending asfar forward as the last of the second set of tnmblers, and ot' the samewidth as the notches in the tnmblers. This slot may be made in twoportions in dierent parts ofthe case, but

is preferably placed as shown, and is for the purpose of receiving inits larger and deeper part the teeth of the rack, hereinafter described,by means of which the case A, containing the locks, is secured in thedoor, and in its smaller and inside portion the end of the door-boltswhen thrown back to open the door.

The part H is solid metal, its quality depending upon the thickness ofthe door, its presence being to afford security against drilling.

rlhe cylinder E is preferably constructed of steel, and is formed `witha flange, e, on its inner end, by which it is secured to the door. Onthe inside of cylinder E is secured iii any position, but preferably asnear the inner end as possible, a toothed rack, j', the teeth g ot'which are tted to engage with the' tumblers h of the secondary lock N.

A safe, vault, or other door has an aperture to receive the cylinder E,whichis placed there- :in and secured by the tlange c, or any othersuitable manner. AThe tumblers h 'i being arranged with their notches inline with the slot F, the teeth g and the end of the door-bolt will passalong the slot F, and the case A can be inserted within the cylinder E.When in position the case A is secured by (logging the tuinblers ofthesecondary lock N by the teeth y, as shown, using the inside dial, whichdoes not move except to operate the secondary lock. The outer dial isremoved and replaced by use of screw g'.

lt` will be seen from the foregoing that the lock N is only to be usedshould the ordinary lock, 0, fail to operate. Then, by means ofthe slotF and teeth g, the whole device can be withdrawn from the door. Theliability of the secondary lock to become deranged is very slight, as inordinary cases it will be so seldom required. The door-bolts should workinto the inner end of slotJ F, which is controlled by the lock O, havingthe ordinary external dial-plate. The form of case shown permits the useof bolts of the usual form ot' construction with slight moditications.

IOO

` h, and dial C, substantially as shown and described.

2. A removable lock having an independent set of tumblers adapted toregister with teeth secured to the door, whereby the whole may beremoved Without operating the combination of the main lock,substantially as shown and described.

3. In combination with the lock O, the cylinder E, provided with teethg, adapted to register with the tumbiers of an independent lock, wherebythe locks are detachably secured in the door, substantially as shownrand'deseribed.`

4. In combination with the lock N, having a cylindrical slotted case,spindle b, and dial 15 C, the toothed cylinder E, substantially as shownand described.

In testimony whereof I have aiXed my signature in presence of twowitnesses.

ROBERT W` THURMAN.

Witnesses: l

JOSEPH GARNEY, G. R. LYMAN.

